Patent US3147531A successfully refreshed from Google Patents.
US3147531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Form for recessed concrete stairway
Assignee: Individual
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Filing: 1963-08-23
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Granted: 1964-09-08
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Expires: 1983-08-23
Abstract
No abstract record available.
Inventors
- 👤 William C Lyons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:11
CPC Classifications
E; E04; E04G; E04G13/00; E04G13/06; E04G13/062
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
177 words
A DEMOUNTABLE FORM FOR A RECESSED CONCRETE STAIRWAY INTENDED TO PROVIDE OUTSIDE ACCESS TO INTERIOR BUILDING AREAS WHOLLY OR PARTLY BELOW GRADE HAVING A VERTICAL WALL WITH AN ACCESS OPENING THEREIN, SAID FORM COMPRISING (A) A FIRST PAIR OF SUBSTANTIALLY TRIANGULAR SIDE WALLS DISPOSED PARALLEL TO EACH OTHER ON OPPOSITE SIDES OF SAID OPENING WITH ONE EDGE PORTION OF EACH SIDE WALL AGAINST THE VERTICAL WALL AND A CONTIGUOUS EDGE PORTION OF EACH SIDE WALL DISPOSED AT AN ANGLE CORRESPONDING TO THE ANGLE OF THE SLOPE OF THE STAIRWAY TO BE POURED, (B) A SECOND PAIR OF SUBSTANTIALLY TRIANGULAR SIDE WALLS INTERPOSED BETWEEN THE FIRST PAIR OF SIDE WALLS ON OPPOSITE SIDES OF SAID OPENING, SAID SECOND PAIR OF SIDE WALLS BEING DISPOSED PARALLEL TO SAID FIRST PAIR OF SIDE WALLS AND SPACED THEREFROM SO AS TO DEFINE THEREWITH PARALLEL TRIANGULARLY SHAPED VOIDS FOR THE WALLS OF THE STAIRWAY TO BE POURED, ONE EDGE PORTION OF EACH SIDE WALL OF SAID SECOND PAIR OF SIDE WALLS BEING DISPOSED ALONG THE SLOPE OF THE STAIRWAY TO BE POURED,
Claim 2
Dependent Claim
177 words
A DEMOUNTABLE FORM FOR A RECESSED CONCRETE STAIRWAY INTENDED TO PROVIDE OUTSIDE ACCESS TO INTERIOR BUILDING AREAS WHOLLY OR PARTLY BELOW GRADE HAVING A VERTICAL WALL WITH AN ACCESS OPENING THEREIN, SAID FORM COMPRISING (A) A FIRST PAIR OF SUBSTANTIALLY TRIANGULAR SIDE WALLS DISPOSED PARALLEL TO EACH OTHER ON OPPOSITE SIDES OF SAID OPENING WITH ONE EDGE PORTION OF EACH SIDE WALL AGAINST THE VERTICAL WALL AND A CONTIGUOUS EDGE PORTION OF EACH SIDE WALL DISPOSED AT AN ANGLE CORRESPONDING TO THE ANGLE OF THE SLOPE OF THE STAIRWAY TO BE POURED, (B) A SECOND PAIR OF SUBSTANTIALLY TRIANGULAR SIDE WALLS INTERPOSED BETWEEN THE FIRST PAIR OF SIDE WALLS ON OPPOSITE SIDES OF SAID OPENING, SAID SECOND PAIR OF SIDE WALLS BEING DISPOSED PARALLEL TO SAID FIRST PAIR OF SIDE WALLS AND SPACED THEREFROM SO AS TO DEFINE THEREWITH PARALLEL TRIANGULARLY SHAPED VOIDS FOR THE WALLS OF THE STAIRWAY TO BE POURED, ONE EDGE PORTION OF EACH SIDE WALL OF SAID SECOND PAIR OF SIDE WALLS BEING DISPOSED ALONG THE SLOPE OF THE STAIRWAY TO BE POURED,
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-09-08 | 1968-03-09 | 1968-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-09-08 | 1972-03-09 | 1972-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-09-08 | 1976-03-09 | 1976-09-08 | $7700.00 | Window Closed / Lapsed |